About ChemistryGo
Free chemistry calculators for students, educators, and researchers.
What this site is
ChemistryGo is a collection of chemistry calculators that run in your browser and return an answer immediately. There are tools for molar mass, stoichiometry, equation balancing, pH and pOH, dilution, the gas laws, molecular structure viewing, and reaction prediction. Every one of them is free, none of them requires an account, and none of them puts a result behind a signup form.
The site exists because the alternative, for most students, is a search result that either wants payment before showing the answer or shows an answer with no working. Neither helps you learn the material. Our aim is that each page gives you the number you need and also explains where the number came from, so that the tool is useful the first time and unnecessary by the end of the term.
Who runs it
ChemistryGo is built and maintained by Michael Goldsmith, a software developer and sole proprietor based in New Jersey, United States. It started as an experiment in whether a genuinely useful reference tool could be built and given away, and it has stayed free since. There is no company behind it, no venture funding, and no team. That is worth knowing when you judge how quickly a correction will be made: usually fast, but by one person.
How the calculations are done
The calculators are not lookup tables or hard coded answers. Inputs are parsed and computed by established open source scientific libraries running on our server.
- RDKit handles molecular structure parsing, formula interpretation, and the geometry behind the molecule viewer. It is the same cheminformatics toolkit used widely in pharmaceutical research.
- ChemPy performs equation balancing and supports the stoichiometric and solution chemistry routines.
- Standard IUPAC atomic weights underpin the molar mass calculations, so a result here matches what a periodic table in a textbook would give you.
Using established libraries rather than hand written arithmetic matters for accuracy. It means an unusual formula, an uncommon isotope, or an awkward equation is handled by code that has already been tested against far more cases than one developer could write by hand.
Accuracy and its limits
The calculators are accurate for the assumptions they state. Those assumptions are real and worth reading. The pH calculator, for example, treats strong acids and bases as completely dissociated and assumes a temperature of 25 degrees Celsius. The ideal gas law calculator assumes ideal behaviour, which departs from reality at high pressure and low temperature. Where an assumption materially changes the answer, the page says so.
ChemistryGo is a study and reference aid. It is not a substitute for laboratory judgment, a validated analytical method, or your institution's safety procedures. Do not rely on it as the sole basis for preparing a reagent that matters, and never as a safety control. If a result looks wrong, it may be, and we would like to hear about it.
Corrections
If you find an error, whether in a calculated result or in the explanatory text on a page, please report it to contact@chemistrygo.com. Include the inputs you used and the answer you expected. Corrections to the chemistry take priority over everything else on the roadmap, because a reference tool that is quietly wrong is worse than no tool at all.
How the site is paid for
Running the site costs money for hosting and a domain. We intend to cover that through advertising. There is no paid tier, no premium calculator, and no plan to put existing functionality behind a payment. If advertising ever fails to cover the cost, the honest outcome would be to say so rather than to start charging for something described as free.
Our privacy policy describes exactly what the site does and does not collect, and our terms of use set out the conditions of use.